What exactly is the idea?  Do you want to have this operating in the debugger (something like having a breakpoint at every use/require), or do you just want to know the list of modules which have been loaded in the end, together with their paths?

In case of the latter, you could maybe just inspect %INC.

Personally, I also like strace -efile ... for similar purposes, because it not only tells me the paths where the modules have been loaded from (including the .so files, in case of XS modules), but also all the paths that had been tried, etc.